Switch comprising an operating rocker button

ABSTRACT

The invention relates to a switch including an operating rocker button and at least one contact element which can be actuated by a radial deflection of the operating rocker button. The contact element can be actuated directly by the operating rocker button, or by the operating rocker button by means of a transmission element. According to the invention, a locking function is provided via a projection on the transmission element or the operating rocker button, which co-operates with an elastic element.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of international applicationPCT/DE2003/002752, filed on Aug. 18, 2003, which designated the UnitedStates and was pending at the time of designation; and further claimspriority to German patent applications 10242273.7, filed Sep. 10, 2002,and 10242532.9, filed Sep. 12, 2002, all of which are hereinincorporated by reference.

BACKGROUND OF THE INVENTION

The invention relates to a switch having an operating rocker, in which acontact element can be operated by radial deflection of the operatingrocker, and in which the operation of the contact element can be carriedout by the operating rocker or by the operating rocker via atransmission element. In the prior art in this case, latching functionsare provided by means of metallic lever and/or spring elements, whichrelease a latching and snap-action mechanism.

SUMMARY OF THE INVENTION

The object of the present invention is to describe a switch having anoperating rocker and latching functions but with a simpler construction.This object is achieved in that the latching function can be provided bya projection on the operating rocker or on the transmission elementinteracting with a sprung element. Since the projection can be insertedinto the operating rocker or into the transmission element, it ispossible to provide both latching and momentary-contact functions withone switch type, depending on whether the projection is or is notinserted. The sprung element has a particularly simple construction bybeing in the form of part of a switching mat. This means there is noneed for any additional element. If the switching mat is formed fromrubber or synthetic rubber, for example silicone, this leads to apermanent spring element. The sprung element is particularly functionalif it has a structure whose cross section is in the form of waves and/ora sawtooth pattern. If the projection is in the form of a roller, thisroller can on the one hand easily overcome the waves or sawteeth duringoperation of the operating aid, while nevertheless firmly holding theswitch in the desired position in the wave troughs of the corrugatedstructure or in indentations in the sawtooth structure. If the switchhas two projections and two contact elements, two switching operationscan be carried out with one switch. In this case, if rollers are used asthe projections, a latching or momentary-contact function of the switchcan be provided depending on whether the roller is or is not inserted.When no rollers are present, a switch can thus be produced with twomomentary-contact functions; when one roller is inserted, a switch canbe produced with a latching and a momentary-contact function, and whenboth rollers are inserted, a switch can be produced with two latchingfunctions. If the transmission element is in the form of a light box,this provides an additional function with one component.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The invention will be explained in more detail in the following textwith reference to the figures, in which:

FIG. 1 shows the cross section through one particularly preferred switchaccording to the invention,

FIG. 2 shows a plan view of a switching mat as illustrated in FIG. 1,

FIG. 3 shows the detail X from FIG. 1, and

FIG. 4 shows a partial section through the switch from FIG. 1 in a firstlatching switching position.

DETAILED DESCRIPTION OF THE INVENTION

The particularly preferred exemplary embodiment of a switch according tothe invention has an operating rocker 1, transmission elements in theform of light boxes 2, a switching mat 3, a printed circuit board 4 anda housing 5. The operating rocker 1 has tabs 1 a, 1 b and twoprojections in the form of rollers 6, 7. The operating rocker 1 can bedeflected radially about an axis A. The switching mat 3 has keys 8 withkey heads 9 which are connected via key feet 10 to a base plate 11 ofthe switching mat 2. Between the keys 8, the switching mat 2 has asprung element 12 with a surface 13 having a cross section in the formof waves. The sprung element 12 has a cavity 14 between its lower faceand the printed circuit board 2. Contact elements 15 are arranged on thelower faces of the key heads 9 and may be composed, for example, ofcarbon or conductive rubber.

The lower faces of the light boxes 2 rest on the upper faces of the keyheads 9. Light-emitting diodes 16 and contact surfaces 17 a-d arearranged on the printed circuit board 4. The contact surfaces 17 a, band 17 c, d are in each case electrically isolated from one another.

FIG. 2 shows light openings 18 and the position of the contact elements14 in the key heads 9; the figure also shows the corrugated surface 13and the base plate 11.

In FIG. 3, the rollers 5, 6 are each illustrated twice; shaded in oneposition which corresponds to the position in FIG. 1, and not shaded inthe position which would correspond to the position if pressure wereapplied to the right-hand side of the surface of the operating rocker 1,thus pushing the right-hand key head 9 downwards with its contactelement 15 electrically connecting the contact surfaces 17 c, d to oneanother. Since the roller 17 is located in the central trough in thecorrugated surface 13, the roller 7 and hence the operating rockermaintain their position.

FIG. 4 shows the switch from FIG. 1 in a switching position which occurswhen pressure has already been applied to the left-hand side of thesurface of the operating rocker 1. The roller 6 is latched in thecentral wave trough of the corrugated surface 13 of the sprung element12. Thus, via the tab 1 a, the operating rocker 1 presses the left-handlight box 2 against the surface of the right-hand key head 9 in such away that the key feet 10 bend in, and the contact element 15electrically connects the two left-hand contact surfaces 17 a, b on theprinted circuit board 5 to one another. The light-emitting diodes 16which are arranged in front of the contact surfaces 17 a, b are notshown, to assist clarity. The illumination of pictograms 18 which arearranged in the operating rocker 1 is shown on the right-hand side inFIG. 4: light beams 20 from the light-emitting diodes 16 pass throughthe light openings 18 through the right-hand light box 2 and illuminatea pictogram 19 in the operating rocker 1. The left-hand pictogram 19 isilluminated in a corresponding manner by the light-emitting diodes whichare not shown on the left-hand side. When the operating rocker 1 isoperated in a latched position as illustrated in FIGS. 1, 2 and 4, atleast one roller 6, 7 is located in a wave trough in the corrugatedsurface 13, that is to say the roller 6 as illustrated in FIG. 4, theroller 7 as illustrated in white in FIG. 3 and both rollers 6, 7 asillustrated in black in FIGS. 1 and 2. Rotation of the operating rockerabout the axis A results in at least one of the rollers 6, 7 beingpressed against a rising area of the corrugated surface 13. Startingfrom the switching position illustrated in black in FIG. 1 or FIG. 3,the elasticity of the sprung element 12 pushes the rising surfacedownwards, so that either the roller 6 or the roller 7 moves into thecentral wave trough of the corrugated surface 13. Since one of thecontact elements 15 is then resting on the contact surfaces 17 a, b or17 c, d, the movement cannot be continued, and the switch remains in thelast position even if an operator releases the operating rocker 1, sinceat least one of the rollers 6, 7 is located in a wave trough, so that anadditional force is required to move it to the next wave trough andhence to the next switching position. If one of the rollers 6, 7 is notinstalled, this results in a switch which has a latching function in onedirection and has a momentary-contact function in the other direction.If, for example, the roller 6 is omitted, the switch acts as amomentary-contact switch when pressure is applied to the left-hand sideof the operating rocker since the roller 7 does not need to overcome anyresistance; when pressure is applied to the right-hand side of theoperating rocker as a latching switch, the roller 7 latches in thecentral wave trough. If both the rollers 6, 7 are omitted, this resultsin a pure momentary-contact switch. Thus, depending on which of therollers 6, 7 is or are fitted to the operating rocker 1, this may resultin a pure latching switch, a pure momentary-contact switch or a combinedlatching/momentary-contact switch. The elasticity of the sprung element12 can be modified by the choice of material and by the configuration ofthe element, in particular by its thickness, the depth of the wavetroughs and the height of the wave peaks that have to be overcome. Theelasticity can also be influenced by varying the cavity 14.

1. A switch, comprising: an operating rocker, at least one contactelement arranged to be operated by radial deflection of the operatingrocker, the contact element arranged to be operable by the operatingrocker or by the operating rocker via a transmission elemental, and alatching functionality provided by a projection on the transmissionelement or on the operating rocker interacting with a sprung element. 2.The switch according to claim 1, wherein the projection is arranged soas to be inserted into the operating rocker or into the transmissionelement.
 3. The switch according to claim 1, wherein the sprung elementcomprises a switching mat.
 4. The switch to claim 3, wherein theswitching mat comprises synthetic rubber or rubber and has at least onecontact element comprising electrically conductive material.
 5. Theswitch claim 3, wherein the sprung element comprises a surface with across section in the form of waves or a sawtooth pattern.
 6. The switchaccording to claim 1, wherein the projection is a roller.
 7. The switchaccording to claim 1, wherein the switch comprises two projections andtwo contact elements.
 8. The switch according to claim 1, wherein thetransmission element comprises a light box.
 9. The switch according toclaim 4, wherein the sprung element comprises a surface with a crosssection in the form of waves or a sawtooth pattern.